Despite its high cost, amorphous metal is gradually replacing electrical grade steel in transformer cores because it is a lower loss material. A wound core transformer can be made from amorphous metal by winding an amorphous metal sheet into a core, cutting one leg of the core, and forming the metal into a rectangular shape. The amorphous metal is then annealed, which converts it into a very brittle material. At this point, the core, except for the cut leg, may be protected by the application of a resinous coating. This prevents damage to the core and the escape of broken fragments of amorphous metal into the transformer where they might cause shorts. The cut leg is opened, coils are placed over other legs of the core and the cut leg is closed and sealed. (See, for example, copending U.S. Pat. application Ser. No. 07/079,854, filed Jul. 30, 1987, titled "Preparation of Amorphous Metal Core for Use in Transformer," herein incorporated by reference.) The final assembly is accomplished by placing the core with the coils mounted over its legs into a tank of oil where it is tested at high voltage. If the transformer fails due to a defect in one of the coils, however, the core must be scrapped because the amorphous metal core cannot be disassembled without damage. While the percentage of defective transformers is very low, the high cost of the amorphous metal cores means that a significant loss is incurred when a core must be scrapped.